diff --git a/swh/storage/writer.py b/swh/storage/writer.py
index 8b2534a9..2f1e110d 100644
--- a/swh/storage/writer.py
+++ b/swh/storage/writer.py
@@ -1,99 +1,101 @@
 # Copyright (C) 2020 The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 from typing import Iterable, Union
+
+from attr import evolve
+
 from swh.model.model import (
     Origin, OriginVisit, Snapshot, Directory, Revision, Release, Content
 )
 
 try:
     from swh.journal.writer import get_journal_writer
 except ImportError:
     get_journal_writer = None  # type: ignore
     # mypy limitation, see https://github.com/python/mypy/issues/1153
 
 
 class JournalWriter:
     """Journal writer storage collaborator. It's in charge of adding objects to
     the journal.
 
     """
     def __init__(self, journal_writer):
         if journal_writer:
             if get_journal_writer is None:
                 raise EnvironmentError(
                     'You need the swh.journal package to use the '
                     'journal_writer feature')
             self.journal = get_journal_writer(**journal_writer)
         else:
             self.journal = None
 
     def content_add(self, contents: Iterable[Content]) -> None:
         """Add contents to the journal. Drop the data field if provided.
 
         """
         if not self.journal:
             return
-        for item in contents:
-            content = item.to_dict()
-            if 'data' in content:
-                del content['data']
-            self.journal.write_addition('content', content)
+        contents = [evolve(item, data=None) for item in contents]
+        self.journal.write_additions('content', contents)
 
     def content_update(self, contents: Iterable[Content]) -> None:
         if not self.journal:
             return
         raise NotImplementedError(
             'content_update is not yet supported with a journal writer.')
 
     def content_add_metadata(
             self, contents: Iterable[Content]) -> None:
         return self.content_add(contents)
 
     def skipped_content_add(
             self, contents: Iterable[Content]) -> None:
-        return self.content_add(contents)
+        if not self.journal:
+            return
+        self.journal.write_additions('content', contents)
 
     def directory_add(self, directories: Iterable[Directory]) -> None:
         if not self.journal:
             return
         self.journal.write_additions('directory', directories)
 
     def revision_add(self, revisions: Iterable[Revision]) -> None:
         if not self.journal:
             return
         self.journal.write_additions('revision', revisions)
 
     def release_add(self, releases: Iterable[Release]) -> None:
         if not self.journal:
             return
         self.journal.write_additions('release', releases)
 
     def snapshot_add(
             self, snapshots: Union[Iterable[Snapshot], Snapshot]) -> None:
         if not self.journal:
             return
         snaps = snapshots if isinstance(snapshots, list) else [snapshots]
         self.journal.write_additions('snapshot', snaps)
 
     def origin_visit_add(self, visit: OriginVisit):
         if not self.journal:
             return
         self.journal.write_addition('origin_visit', visit)
 
     def origin_visit_update(self, visit: OriginVisit):
         if not self.journal:
             return
         self.journal.write_update('origin_visit', visit)
 
     def origin_visit_upsert(self, visits: Iterable[OriginVisit]):
         if not self.journal:
             return
         self.journal.write_additions('origin_visit', visits)
 
     def origin_add_one(self, origin: Origin):
         if not self.journal:
             return
         self.journal.write_addition('origin', origin)